Method of making a rubberized fiber composition



Oct; 19 1926. 1,603,335

J. M. GILLET METHOD OF MAKING A RUBBERIZED FIBER COMPOSITION Fild July 31, 1922 O INVENTOR $7,115 11% 69.4157

Patented Got. 19, 12,.

8mm M. GILLET, OE MILWAUKEE, WISCGNSIN, ASSIGNGR TO THE GOODYEAR TIB JE 8t RUBBER CDMIPANY, OF AKRON, QHIO, A CORPORATION OHIO.

EETHQD OF MAKING A RUBBERIZED FIBER CQIEPQSITION,

Application filed July 31,

My invention relates to the methodof making a rubberized fiber composition which may be utilized in a variety out capacities, such as for fioor or wall coverings,

5 as a substitute for leather, or for any purpose to which a tough, flexible Porous, water-resistant body may be adapted.

More particularly,'my invention relatesto that portion of the method designated in 10 which rubber is precipitated from a solution, eitherupon a mass of fibers suspended and dispersed in said solution or from a solution free from any suspended matter.

My invention particularly contemplates precipitating rubber from a liquid containing rubber in solution bycontrolling the temperature of said liquic Heretofore, it has been customary to precipitate rubber from solution, such, for ex ample, as toluol or benzol, by the addition of a precipitating agent, such as alcohol While the rubber may be successfully precipitated by this method, the amount of alco- "hol necessary to produce complete precipitation, within a sutficiently short time for commercial purposes, is relatively large. Furthermore, after the rubber has been precipitated, there remains'a liquid which is a mixture of bend. and alcohol, and'a small amount of the constituents of rubber which are soluble in alcohol.

As it is necessary to dissolve the rubber before it can be precipitated in any desired manner, the solution remaining after the previously described process has been completed, cannot be utilized again for the same purpose on account of the high percentage of alcohol added to produce precipitation and which prevents the dissolution of the rubber. It is, therefore, necessaryeither to use fresh .be'nzol and alcohol, which would be very expensive on account of the large quantities employed, or to separate the solvent from the precipitating agent, the cost of which is also a material item.

By my invention I have overcome the necessity of adding to the solution any agent tending to produce precipitation other than a relatively small quantity of alcohol, which may be added during the mixing process and which does not prevent the proper dissolution of the rubber in the benhol so long as the liquid is maintained t the proper temperature. By properly temperature of the liquid, piecipitation is ntrolling the a 1922. Serial No. 573,786.

produced in any desired degree and, within certain limits, in any desired interval of a relatively smaller quantity of alcohol, or:

other rubber precipitant. To this liquid a suitable quantity of rubber cement is added, which is dissolved therein. A quantity of fibers,v either of cotton, hemp, manila, 1ute, asbestos, wood or the like, is then added to the liquid and is beaten and separated so as to curl and fray the ends thereof, the beating action serving to thoroughly mix and dispcrse the fibers throughout .the liquid. While the rubber is mentioned as being added to the solution prior to the addition of the fibers, it might equally Well be addedsub-sequently thereto. essary for the preparation of the material have now been added, and all at approxi mately the same time. The mixture is maintained at a temperature above a critical point, which varies with the relative qaantities of solvent and precipitant present, until the rubber is thoroughly dissolved. The temperature of the mixture is then lowered to produce precipitation. By properly regulating the rate of change of the temperature, the period of time. required for complete precipitation may, within certain limits be controlled at-will, and be made of sufficiently short duration for commercial purposes.

As an example, if 1152 cc. of toluol is mixed with 448 cc. of alcohol, and has added thereto S gr. of rubber and 8 gr. of fibers, the rubber will be readily dissolved at about 62 C. or above. If the temperature of the,

mixture is then lowered, while being stirred gently, to about 25 C. the rubber is precipitated upon the individual fibers, iorming a coating thereon. The coated fibers are then strained out of the solution on a screen, washed with a small quantity of alcohol, pressed and dried. The resulting matis then cured under pressure at a temperature.

relatively high Itltlfill mil

Thus, 5m 0111; "mass is in the tem'oer Ihe iiquid remainin gprecipi'mte mbbei" 1Q cmzsists of the S21E19 galvemt anti preciyitamb me sol'iutian way, 533% The. mail and agsmn. Agapmxmm. cc. f

iiquici musvfi be aided for new mat, 0i fine size. in questicn 15.115 amount, Qeing' mac-n essay to keep 131w mm; 1600 cm, tbs mig inai ameunt.

Efha reflective qua-nt-iii s 'presrlpitzmfi @1105. determine vulture at Whiih flawed This reiatifln is indicated in m alcc ompimymg Winch relatea a wiuuhilwhni. soiluiion. As inciicavad kg 5218 leguds, curve Aqrepzesenm the tenm peratures, for the various ssiuions at which jcipitation starts. Guav mpresen'fis various temperatures 1.1 filirsh complete ipitation 00mm, (1212 G mpresents 'vm'ius temperatures at which initial 1e-s0uti0n occurs. Curve reptsesents m piarawgures at 'Whifiil Coilglam m-selutien '11 be noted thu in "'aha bas cs x-emrdefi, "Awe. repressniing imitiali. presipiafiatian 23$", mrrespend. to that. represeming & E'Qfifihfif-iOH, nor (was the curve mp piee precipitation. ceinsids L resenting' initial re-soluiiam Thfififi *3 iifierences are believed i0 be caused by film as of prspm' agitation c1121 th s was an process.

4123* -J it is gmssibie t0 determine wrmt ammm s (2f who may used vitiqmiflue rubber at any givsm tampmratmre i0 3 what tempam tum is .Qecessar to SlbhQ] salve 01' ggrmiyfi mm the rubber Wham 81s psmenmg- 05am hm greseni is'kncwxs. 1

By utiiiza 0i? zzim'ezmemiomzi prmzm s sevemi'a-i mmag az scram, mi which the mnsi; impoflant is face; ihfiii approx? 62% of the iiig uicis usai 38m;- ena mat may be. used in making" 113 next mafia witheut-any preparation 01" sepam'cion finereoit' whaiso'ever. Anaishar advantaga is that, sinca all the necessary ing'redieni 's are mlxefi togeaher at 011;; fumeflhe fibers becsma tlmrmlghly and equally dir'apersed thmugh out the (a "3% liquid ami a uniform precipimtiml 0f 1. fiber m1 she fibez' is secure, h 2% high aoucanfiyation of 9.1201101 is amidiafi, and the amoum 01f aicohei necessm v is mmzerially mducaii. v

Ax inspeetion 013 the dmwin inrii-c that the miation 05? any 021% sat cam-ET tampemtures andl pamenit ampla, as the initial yresi m an temperw turns in the. cerraspsnaing 2323's 'mgeg m aiwho! in tha ssiutlon may 'sfwpwsm c'ad 2210?) pxeeipi'zaiiun provided the percent of.

Mambo? present known, 0r vice versa. Using the twopeint straight line equaticn, appiied t0 the initial precigfi'mticn curv, after: assuming two points and M. Lei) w paarcentage 0f alcohol in solution and. yxdsgmes 0f tem oemture Centigrade let the paint L be represened by Mm g representing mspegtively 30% aicohol soluiion and *31" Centigrade, mad let the paint M. be repiresentad by 51 and y representing respectively 533% alcaiwl solution and 28 substituiing Either w or 3,1, thai is, the percentage 0f 33001101 present or the initial. precipitation tamperature, the corresponding rmknswn may readily be calculated. In similar manner the 0mm N and *9 may be used sacure a similar equation mlating m the cmmpleize precipitatien curve. This equation besomas fer. givsn percfinmge a'f alcehol, in mfier t0 briizg' about dissniution of the rubber and in order t0 prevent pz'eoipifiatien thereei, tbs suiution shank} be maintained ahavs ishe wmpm'atum Y ca'icuiaied by substitutiing 1e percantage of alcshol fur in gm ezquam 11 m insure campfiete) precipimizian flag s0- zdumi as fisha wiveni rubber aged and to pitana, it is amuse, may beam gasahm vdzz; 25nd ywa'mma 0213 the h3 5 i213 mail a,

tions and changes may be made therein without departing from the spirit and scope of the appended claims.

What I claim is:

1. The method of controlling the precipitation of rubber in solution which comprises regulating the temperature of said solution. 2. The method of effecting the precipitation of rubber out of a mixture containing rubber in solution which comprises lowering the temperature of said solution.

3. The method of controlling the rate of precipitation of rubber out of a mixture containing rubber in solution which comprises controlling the temperature of saidsolutioin.

4:. he method of controlling the precipitation of rubber in a solution comprising a rubber solvent and a rubber precipitating agent which comprises regulating the temperature of said solution.

5. The method of treating a mixture enibodying rubber which comprises maintaining the temperature ofthe solution at a ,sufliciently high degree of temperature to effect dissolution of said rubber and subsequently to a relatively lower degree of tem- "her.

6. The method of controlling the precipi-' tation of rubber in a toluol-alcohol solution which comprises controlling the temperature of said solution.

7. The method of effecting the precipitation of rubber out of a toluol-alcoho1 solution which comprises reducing the tempera ture of the solution below a critical point, said point being-determined by the relative proportions of alcohol and toluol present in the solution.

8. The method of treating fibers which comprises beating the fibers in a solventrecipitant liquid containing rubber, which iquid dissolves said rubber when raised above a predetermined critical temperature and causes said rubber to be precipitated upon said fibers when reduced below a pre determined critical temperature said point being determined by the relative proportions of solvent and precipitant present. in the liquid.

9. The method of treating fibers which comprises immersing the fibers in a liquid containing rubber, a rubber solvent and a rubber precipitating agent, beatin fibers in said solution, and loweringt etemperature of said solution to effect precipitation of the rubber on the. fibers v 10. The method of making a mat which comprises mixing togethen'a quantit of fibers, a uantity of rubber, a rubber so vent I and a. In her precipitating agent, maintainquently lowerin .mixture until t e rubber is precipitated said ing said mixture at a suliiciently high temperature to dissolve the rubber and subsethe temperature of said from said solution upon said fibers.

11. The method of making a fibrous mat which comprises'mixi'n'g aquantity of fiber having curled and frayed ends and a quan tity of rubber compound in a solution ct toluol and alcohol, maintaining said solution above a sufficientl high degree of temperature to dissolve t e rubber and subse quently lowerin the temperature of said solution until t he rubber is precipitated upon said'fibers.

12. The method of treating a solution comprising approximately 25% rubber precipi'tant and approximately rubber solvent, which comprises mixing a quantity of rubber therewith, maintaining sa1d solution above approximately 45? C. to produce dissolution ofthe rubber and reducing said solution below appnoximately 30 C. to produce precipitation of the rubber out oi the solution. y

13. The method of treatinga rubber solution comprising toluol and alcohol which comprises efiecting dissolution of the rubber by raising said solution above a temperature represented approximately in degrees I centigrade by Y in the equation in' which a: re resents percent alcohol in solution and e ecting precipitation of the rubber out of the solution by reducing solution beloyv a temperature represented approximately by Y in the equation 14. A method of making rubberized fibrous composition that comprises treating rubber with a solvent, mixinga fibrous ma terial therewith and precipitating the rub her by chilling the suspension.

15. A .method :of making rubberired fibrous composition that comprises dissolving rubber in a fluid exhibiting a solvent action at elevated temperatures, incorpcrating a fibrous material therewith and I rubber in a mixture of alcohol and JAMES. a. crater. 

